1. Field of the Invention
The present invention relates generally to industrial safety devices. More particularly, the present invention relates to a lockout system and apparatus for use with industrial equipment and energy sources.
2. Description of the Prior Art
Energy sources in machines and equipment is a hazard to workers. Energy sources include electrical, mechanical, hydraulic, pneumatic, chemical, and thermal energy sources. Workers servicing or maintaining machines or equipment must properly control energy sources to avoid accidents. While servicing and maintaining machines and equipment, for example, an unexpected machine startup or release of stored energy can result in serious injury or death to workers. Injuries resulting from a failure to control hazardous energy during maintenance activities can be fatal and include burns, crush injuries, cuts, lacerations, amputations, and bone fractures.
For example, a steam valve opened automatically can burn workers who are repairing a downstream connection in the piping. A jammed conveyor system can suddenly release and crush a worker attempting to clear the jam. Internal wiring on factory equipment can electrically short, causing electric shock to the worker who is performing a repair.
Industrial workers, electricians, machine operators, and laborers are among the millions of workers who service equipment routinely and face the greatest risk of injury. A worker injured on the job from exposure to hazardous energy will require an average of 24 work days to recuperate from injuries. This recuperation time is costly in the form of lost productivity, medical expenses, lost revenue, other expenses, and as reduced morale after an accident.
To properly control hazardous energy and protect workers from these hazards, lockout/tagout (LOTO) practices and procedures have been established by the Occupational Safety and Health Administration (OSHA). OSHA's regulation is titled Control of Hazardous Energy and is published as 29 C.F.R. §1910.147. This regulation outlines specific action and procedures for addressing and controlling hazardous energy during service and maintenance of machines and equipment used in general industry. Employers are required to train each worker to ensure that they know, understand, and are able to follow the applicable provisions of the hazardous energy control procedures. Requirements include knowing the purpose and function of the energy control program and having the knowledge and skills to safely apply, use, and remove energy control devices.
All employees who work in an area where energy control procedure is utilized need to be instructed in the purpose of and procedure to control energy, especially the prohibition against attempting to restart or reenergize machines or other equipment that are locked or tagged. All employees who are authorized to lockout machines or equipment and perform the service and maintenance operations need to be trained to recognize hazardous energy sources in the workplace, the type and magnitude of energy found in the workplace, and the appropriate means and methods of isolating and/or controlling the energy.
Proper procedure for controlling energy includes using lockout/tagout devices to shut down equipment and machines for service or repair. FIG. 1 shows an example of a prior art lockout/tagout kit 10 that includes a hasp 12, a plurality of tags 20, and a plurality of locks 30. Hasp 12 has two hasp parts 12a, 12b, each of which has a hook portion 14 and a body portion 16 with openings 17. Hasp parts 12a, 12b rotate about a connector 18 between an open position and a closed position. In the closed position as shown in FIG. 1, the hook portions 14 are brought together to define a closed loop that may be installed through an equipment switch. In the closed position, the body portions 16 also overlap with the openings 17 aligned so that a lock 30 can be fastened through each opening 17 to prevent the hasp 12 from being opened. Each worker servicing a machine or piece of equipment will attach a lock 30 to the hasp 12 while servicing a machine. Each worker removes his lock 30 when his service has been completed. After all locks 30 have been removed, the machine is now available for use.
In the open position, hasp parts 12a, 12b rotate about connector 18 in opposite directions so that the hook portions 14 open and the body portions 16 move away from each other. When all locks 30 are removed from the hasp 12, hasp parts 12a, 12b can be moved to the open position so the hasp 12 can be removed from the equipment.
FIG. 2 shows an example of a prior-art method of locking out a valve 24 with a hasp 12 attached to the valve lock 26 and secured with three locks 30 installed through body portions 16. A tag 20 is installed on the pipe next to the valve being locked in a closed position. In many cases, each user installs a tag 20 on the lock 30 to identify the person who installed the lock 30 and the reason for doing so.
FIG. 3 shows another example of a prior-art method of locking an electrical switch 40 in an “off” position using a hasp 12 and locks 30. With one or more locks 30 attached to the hasp 12, the hasp 12 cannot be opened and removed from the switch 40. Accordingly, the switch 40 cannot be operated because the hasp 12 blocks its movement to the “on” position.